Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 72
Filtrar
Mais filtros








Base de dados
Intervalo de ano de publicação
1.
Lab Chip ; 24(11): 2927-2943, 2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38591995

RESUMO

Platelets play an essential role in thrombotic processes. Recent studies suggest a direct link between increased plasma glucose, lipids, and inflammatory cytokines with platelet activation and aggregation, resulting in an increased risk of atherothrombotic events in cardiovascular patients. Antiplatelet therapies are commonly used for the primary prevention of atherosclerosis. Transitioning from a population-based strategy to patient-specific care requires a better understanding of the risks and advantages of antiplatelet therapy for individuals. This proof-of-concept study evaluates the potential to assess an individual's risk of forming atherothrombosis using a dual-channel microfluidic model emulating multiple atherogenic factors in vitro, including high glucose, high cholesterol, and inflammatory cytokines along with stenosis vessel geometry. The model shows precise sensitivity toward increased plasma glucose, cholesterol, and tumour necrosis factor-alpha (TNF-α)-treated groups in thrombus formation. An in vivo-like dose-dependent increment in platelet aggregation is observed in different treated groups, benefiting the evaluation of thrombosis risk in the individual condition. Moreover, the model could help decide the effective dosing of aspirin in multi-factorial complexities. In the high glucose-treated group, a 50 µM dose of aspirin could significantly reduce platelet aggregation, while a 100 µM dose of aspirin was required to reduce platelet aggregation in the glucose-TNF-α-treated group, which proves the model's potentiality as a tailored tool for customised therapy.


Assuntos
Dispositivos Lab-On-A-Chip , Agregação Plaquetária , Trombose , Trombose/tratamento farmacológico , Trombose/prevenção & controle , Humanos , Agregação Plaquetária/efeitos dos fármacos , Inibidores da Agregação Plaquetária/farmacologia , Fator de Necrose Tumoral alfa/sangue , Fator de Necrose Tumoral alfa/metabolismo , Aterosclerose/tratamento farmacológico , Aspirina , Plaquetas/efeitos dos fármacos , Plaquetas/citologia
2.
Adv Biol (Weinh) ; 8(4): e2300463, 2024 04.
Artigo em Inglês | MEDLINE | ID: mdl-38200677

RESUMO

Monocyte recruitment and transmigration are crucial in atherosclerotic plaque development. The multi-disease complexities aggravate the situation and continue to be a constant concern for understanding atherosclerosis plaque development. Herein, a 3D hydrogel-based model that integrates disease-induced microenvironments is sought to be designed, allowing us to explore the early stages of atherosclerosis, specifically examining monocyte fate in multi-disease complexities. As a proof-of-concept study, murine cells are employed to develop the model. The model is constructed with collagen embedded with murine aortic smooth muscle cells and a murine endothelial monolayer lining. The model achieves in vitro disease complexities using external stimuli such as glucose and lipopolysaccharide (LPS). Hyperglycemia exhibits a significant increase in monocyte adhesion but no enhancement in monocyte transmigration and foam cell conversion compared to euglycemia. Chronic infection achieved by LPS stimulation results in a remarkable augment in initial monocyte attachment and a significant increment in monocyte transmigration and foam cells in all concentrations. Moreover, the model exhibits synergistic sensitivity under multi-disease conditions such as hyperglycemia and infection, enhancing initial monocyte attachment, cell transmigration, and foam cell formation. Additionally, western blot data prove the enhanced levels of inflammatory biomarkers, indicating the model's capability to mimic disease-induced complexities during early atherosclerosis progression.


Assuntos
Aterosclerose , Hiperglicemia , Placa Aterosclerótica , Animais , Camundongos , Células Espumosas/metabolismo , Hidrogéis , Lipopolissacarídeos/farmacologia , Lipopolissacarídeos/metabolismo , Aterosclerose/metabolismo , Placa Aterosclerótica/metabolismo
3.
Adv Healthc Mater ; 13(1): e2301039, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37725037

RESUMO

The use of biomaterials in implanted medical devices remains hampered by platelet adhesion and blood coagulation. Thrombus formation is a prevalent cause of failure of these blood-contacting devices. Although systemic anticoagulant can be used to support materials and devices with poor blood compatibility, its negative effects such as an increased chance of bleeding, make materials with superior hemocompatibility extremely attractive, especially for long-term applications. This review examines blood-surface interactions, the pathogenesis of clotting on blood-contacting medical devices, popular surface modification techniques, mechanisms of action of anticoagulant coatings, and discusses future directions in biomaterial research for preventing thrombosis. In addition, this paper comprehensively reviews several novel methods that either entirely prevent interaction between material surfaces and blood components or regulate the reaction of the coagulation cascade, thrombocytes, and leukocytes.


Assuntos
Coagulação Sanguínea , Trombose , Humanos , Trombose/prevenção & controle , Anticoagulantes/farmacologia , Materiais Biocompatíveis/farmacologia , Plaquetas , Propriedades de Superfície
4.
Artigo em Inglês | MEDLINE | ID: mdl-38038959

RESUMO

Gas therapy has gained noteworthy attention in biomedical research, with the rise of gas-releasing molecules enhancing their therapeutic potential, especially when integrated into nano-based drug delivery systems. Herein, we present a lipid-coated gas delivery system to simultaneously shuttle two gas-releasing molecules carrying nitric oxide (NO) and carbon monoxide (CO), respectively. Upconversion nanoparticles (UCNPs) are designed to generate photons at 360 nm upon 808 nm of near-infrared (NIR) irradiation. These in situ-generated UV photons trigger simultaneous NO and CO release from S-nitrosoglutathione (GSNO) and the CO-releasing molecule (CORM), respectively, which are coloaded into lipid-coated UCNP/GSNO/CORM/FA nanoparticles (LUGCF). LUGCF with a GSNO/CORM mass ratio of 2:1 is determined to be optimal in terms of synergistically instigating apoptosis in HCT116 and CT26 colon cancer cells, where both NO/CO are released and subsequent production of ROS are detected. This CO/NO combination nanoplatform exhibits a very effective inhibition of colon tumor growth in vivo at relatively low doses upon a mild 808 nm irradiation. Overall, we effectively integrated two therapeutic gas-releasing molecules in one NIR-responsive nanosystem, presenting a promising therapeutic strategy for future biomedical applications in dual-gas cancer therapy.

5.
Nanotechnology ; 35(5)2023 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-37863070

RESUMO

Currently, the treatment for acute disease encompasses the use of various biological drugs (BDs). However, the utilisation of BDs is limited due to their rapid clearance and non-specific accumulation in unwanted sites, resulting in a lack of therapeutic efficacy together with adverse effects. While nanoparticles are considered good candidates to resolve this problem, some available polymeric carriers for BDs were mainly designed for long-term sustained release. Thus, there is a need to explore new polymeric carriers for the acute disease phase that requires sustained release of BDs over a short period, for example for thrombolysis and infection. Poly(succinimide)-oleylamine (PSI-OA), a biocompatible polymer with a tuneable dissolution profile, represents a promising strategy for loading BDs for sustained release within a 48-h period. In this work, we developed a two-step nanoprecipitation method to load the model protein (e.g. bovine serum albumin and lipase) on PSI-OA. The characteristics of the nanoparticles were assessed based on various loading parameters, such as concentration, stirring rate, flow rate, volume ratio, dissolution and release of the protein. The optimised NPs displayed a size within 200 nm that is suitable for vasculature delivery to the target sites. These findings suggest that PSI-OA can be employed as a carrier for BDs for applications that require sustained release over a short period.


Assuntos
Aminas , Portadores de Fármacos , Nanopartículas , Humanos , Preparações de Ação Retardada , Doença Aguda , Polímeros , Succinimidas , Tamanho da Partícula
6.
Mater Today Bio ; 22: 100767, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37600355

RESUMO

Atherosclerosis is the build-up of fatty deposits in the arteries, which is the main underlying cause of cardiovascular diseases and the leading cause of global morbidity and mortality. Current pharmaceutical treatment options are unable to effectively treat the plaque in the later stages of the disease. Instead, they are aimed at resolving the risk factors. Nanomaterials and nanoparticle-mediated therapies have become increasingly popular for the treatment of atherosclerosis due to their targeted and controlled release of therapeutics. In this review, we discuss different types of therapeutics used to treat this disease and focus on the different nanomaterial strategies employed for the delivery of these drugs, enabling the effective and efficient resolution of the atherosclerotic plaque. The ideal nanomaterial strategy for each drug type (e.g. statins, nucleic acids, small molecule drugs, peptides) will be comprehensively discussed.

7.
ACS Nano ; 17(19): 18775-18791, 2023 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-37650798

RESUMO

Although poly(aspartic acid) (PASP), a strong calcium chelating agent, may be potentially effective in inhibition of vascular calcification, its direct administration may lead to side effects. In this study, we employed polysuccinimide, a precursor of PASP, to prepare targeted polysuccinimide-based nanoparticles (PSI NPs) that not only acted as a prodrug but also functioned as a carrier of additional therapeutics to provide powerful synergistic vascular anticalcification effect. This paper shows that chemically modified PSI-NPs can serve as effective nanocarriers for loading of hydrophobic drugs, in addition to anticalcification and antireactive oxygen species (anti-ROS) activities. Curcumin (Cur), with high loading efficiency, was encapsulated into the NPs. The NPs were stable for 16 h in physiological conditions and then slowly dissolved/hydrolyzed to release the therapeutic PASP and the encapsulated drug. The drug release profile was found to be in good agreement with the NP dissolution profile such that complete release occurred after 48 h at physiological conditions. However, under acidic conditions, the NPs were stable, and Cur cumulative release reached only 30% after 1 week. Though highly effective in the prevention of calcium deposition, PSI NPs could not prevent the osteogenic trans-differentiation of vascular smooth muscle cells (VSMCs). The presence of Cur addressed this problem. It not only further reduced ROS level in macrophages but also prevented osteogenic differentiation of VSMCs in vitro. The NPs were examined in vivo in a rat model of vascular calcification induced by kidney failure through an adenine diet. The inclusion of Cur and PSI NPs combined the therapeutic effects of both. Cur-loaded NPs significantly reduced calcium deposition in the aorta without adversely affecting bone integrity or noticeable side effects/toxicity as examined by organ histological and serum biochemistry analyses.

8.
Cardiovasc Res ; 119(13): 2278-2293, 2023 10 24.
Artigo em Inglês | MEDLINE | ID: mdl-37595265

RESUMO

Vascular cell adhesion molecule-1 (VCAM-1) has been well established as a critical contributor to atherosclerosis and consequently as an attractive therapeutic target for anti-atherosclerotic drug candidates. Many publications have demonstrated that disrupting the VCAM-1 function blocks monocyte infiltration into the sub-endothelial space, which effectively prevents macrophage maturation and foam cell transformation necessary for atherosclerotic lesion formation. Currently, most VCAM-1-inhibiting drug candidates in pre-clinical and clinical testing do not directly target VCAM-1 itself but rather down-regulate its expression by inhibiting upstream cytokines and transcriptional regulators. However, the pleiotropic nature of these regulators within innate immunity means that optimizing dosage to a level that suppresses pathological activity while preserving normal physiological function is extremely challenging and oftentimes infeasible. In recent years, highly specific pharmacological strategies that selectively inhibit VCAM-1 function have emerged, particularly peptide- and antibody-based novel therapeutics. Studies in such VCAM-1-directed therapies so far remain scarce and are limited by the constraints of current experimental atherosclerosis models in accurately representing the complex pathophysiology of the disease. This has prompted the need for a comprehensive review that recounts the evolution of VCAM-1-directed pharmaceuticals and addresses the current challenges in novel anti-atherosclerotic drug development.


Assuntos
Aterosclerose , Molécula 1 de Adesão de Célula Vascular , Humanos , Molécula 1 de Adesão de Célula Vascular/metabolismo , Endotélio Vascular/metabolismo , Monócitos/metabolismo , Descoberta de Drogas , Adesão Celular
9.
ACS Appl Mater Interfaces ; 15(36): 42153-42169, 2023 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-37602893

RESUMO

Nanophotothermal therapy based on nanoparticles (NPs) that convert near-infrared (NIR) light to generate heat to selectively kill cancer cells has attracted immense interest due to its high efficacy and being free of ionizing radiation damage. Here, for the first time, we have designed a novel nanohybrid, silver-iron oxide NP (AgIONP), which was successfully tuned for strong absorbance at NIR wavelengths to be effective in photothermal treatment and dual-imaging strategy using MRI and photoacoustic imaging (PAI) in a cancer model in vivo and in vitro, respectively. We strategically combine the inherent anticancer activity of silver and photothermal therapy to render excellent therapeutic capability of AgIONPs. In vitro phantoms and in vivo imaging studies displayed preferential uptake of folate-targeted NPs in a cancer mice model, indicating the selective targeting efficiency of NPs. Importantly, a single intravenous injection of NPs in a cancer mice model resulted in significant tumor reduction, and photothermal laser resulted in a further substantial synergistic decrease in tumor size. Additionally, biosafety and biochemical assessment performed in mice displayed no significant difference between NP treatment and control groups. Overall, our folic acid AgIONPs displayed excellent potential in the simultaneous application for safe and successful targeted synergistic photothermal treatment and imaging of a cancer model.


Assuntos
Ferro , Prata , Animais , Camundongos , Prata/farmacologia , Diagnóstico por Imagem , Imagens de Fantasmas , Ácido Fólico
10.
ACS Appl Mater Interfaces ; 15(25): 29777-29788, 2023 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-37318848

RESUMO

Electrohydrodynamic atomization (EHDA) provides unparalleled control over the size and production rate of particles from solution. However, conventional methods produce highly charged particles that are not appropriate for inhalation drug delivery. We present a self-propelled EHDA system to address this challenge, a promising one-step platform for generating and delivering charge-reduced particles. Our approach uses a sharp electrode to produce ion wind, which reduces the cumulative charge in the particles and transports them to a target in front of the nozzle. We effectively controlled the morphologies of polymer products created from poly(vinylidene fluoride) (PVDF) at various concentrations. Our technique has also been proven safe for bioapplications, as evidenced by the delivery of PVDF particles onto breast cancer cells. The combination of simultaneous particle production and charge reduction, along with its direct delivery capability, makes the self-propelled EHDA a versatile technique for drug delivery applications.


Assuntos
Sistemas de Liberação de Medicamentos , Polivinil , Tamanho da Partícula
11.
Cyborg Bionic Syst ; 4: 0036, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37342212

RESUMO

Inertial microfluidics uses the intrinsic fluid inertia in confined channels to manipulate the particles and cells in a simple, high-throughput, and precise manner. Inertial focusing in a straight channel results in several equilibrium positions within the cross sections. Introducing channel curvature and adjusting the cross-sectional aspect ratio and shape can modify inertial focusing positions and can reduce the number of equilibrium positions. In this work, we introduce an innovative way to adjust the inertial focusing and reduce equilibrium positions by embedding asymmetrical obstacle microstructures. We demonstrated that asymmetrical concave obstacles could break the symmetry of original inertial focusing positions, resulting in unilateral focusing. In addition, we characterized the influence of obstacle size and 3 asymmetrical obstacle patterns on unilateral inertial focusing. Finally, we applied differential unilateral focusing on the separation of 10- and 15-µm particles and isolation of brain cancer cells (U87MG) from white blood cells (WBCs), respectively. The results indicated an excellent cancer cell recovery of 96.4% and WBC rejection ratio of 98.81%. After single processing, the purity of the cancer cells was dramatically enhanced from 1.01% to 90.13%, with an 89.24-fold enrichment. We believe that embedding asymmetric concave micro-obstacles is a new strategy to achieve unilateral inertial focusing and separation in curved channels.

12.
Bioact Mater ; 27: 231-256, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37122895

RESUMO

In traumatized patients, the primary cause of mortality is uncontrollable continuous bleeding and unexpected intraoperative bleeding which is likely to increase the risk of complications and surgical failure. High expansion sponges are effective clinical practice for the treatment of wound bleeding (irregular/deep/narrow) that are caused by capillaries, veins and even arterioles as they possess a high liquid absorption ratio so can absorb blood platelets easily in comparison with traditional haemostasis treatments, which involve compression, ligation, or electrical coagulation etc. When in contact with blood, haemostatic sponges can cause platelet adhesion, aggregation, and thrombosis, preventing blood from flowing out from wounds, triggering the release of coagulation factors, causing the blood to form a stable polymerized fibre protein, forming blood clots, and achieving the goal of wound bleeding control. Haemostatic sponges are found in a variety of shapes and sizes. The aim of this review is to facilitate an overview of recent research around haemostatic sponge materials, products, and technology. This paper reviews the synthesis, properties, and characteristics of haemostatic sponges, together with the haemostasis mechanisms of haemostatic sponges (composite materials), such as chitosan, cellulose, gelatin, starch, graphene oxide, hyaluronic acid, alginate, polyethylene glycol, silk fibroin, synthetic polymers silver nanoparticles, zinc oxide nanoparticles, mesoporous silica nanoparticles, and silica nanoparticles. Also, this paper reviews commercial sponges and their properties. In addition to this, we discuss various in-vitro/in-vivo approaches for the evaluation of the effect of sponges on haemostasis.

13.
Res Sq ; 2023 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-37066342

RESUMO

Angiotensin-converting enzyme 2 (ACE2) is protective in cardiovascular disease, lung injury and diabetes yet paradoxically underlies our susceptibility to SARs-CoV2 infection and the fatal heart and lung disease it can induce. Furthermore, diabetic patients have chronic, systemic inflammation and altered ACE2 expression resulting in increased risk of severe COVID-19 and the associated mortality. A drug that could increase ACE2 activity and inhibit cellular uptake of severe acute respiratory syndrome coronavirus 2 (SARs-CoV2), thus decrease infection, would be of high relevance to cardiovascular disease, diabetes and SARs-CoV2 infection. While the need for such a drug lead was highlighted over a decade ago receiving over 600 citations,1 to date, no such drugs are available.2 Here, we report the development of a novel ACE2 stimulator, designated '2A'(international PCT filed), which is a 10 amino acid peptide derived from a snake venom, and demonstrate its in vitro and in vivo efficacy against SARs-CoV2 infection and associated lung inflammation. Peptide 2A also provides remarkable protection against glycaemic dysregulation, weight loss and disease severity in a mouse model of type 1 diabetes. No untoward effects of 2A were observed in these pre-clinical models suggesting its strong clinical translation potential.

14.
Biomater Sci ; 11(6): 1923-1947, 2023 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-36735240

RESUMO

Biological drugs (BDs) play an increasingly irreplaceable role in treating various diseases such as cancer, and cardiovascular and neurodegenerative diseases. The market share of BDs is increasingly promising. However, the effectiveness of BDs is currently limited due to challenges in efficient administration and delivery, and issues with stability and degradation. Thus, the field is using nanotechnology to overcome these limitations. Specifically, polymeric nanomaterials are common BD carriers due to their biocompatibility and ease of synthesis. Different strategies are available for BD transportation, but the use of core-shell encapsulation is preferable for BDs. This review discusses recent articles on manufacturing methods for encapsulating BDs in polymeric materials, including emulsification, nanoprecipitation, self-encapsulation and coaxial electrospraying. The advantages and disadvantages of each method are analysed and discussed. We also explore the impact of critical synthesis parameters on BD activity, such as sonication in emulsifications. Lastly, we provide a vision of future challenges and perspectives for scale-up production and clinical translation.


Assuntos
Nanoestruturas , Neoplasias , Humanos , Nanotecnologia/métodos , Polímeros
15.
Biosensors (Basel) ; 13(1)2023 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-36671971

RESUMO

The human gut is responsible for food digestion and absorption. Recently, growing evidence has shown its vital role in the proper functioning of other organs. Advances in microfluidic technologies have made a significant impact on the biomedical field. Specifically, organ-on-a-chip technology (OoC), which has become a popular substitute for animal models, is capable of imitating complex systems in vitro and has been used to study pathology and pharmacology. Over the past decade, reviews published focused more on the applications and prospects of gut-on-a-chip (GOC) technology, but the challenges and solutions to these limitations were often overlooked. In this review, we cover the physiology of the human gut and review the engineering approaches of GOC. Fundamentals of GOC models including materials and fabrication, cell types, stimuli and gut microbiota are thoroughly reviewed. We discuss the present GOC model applications, challenges, possible solutions and prospects for the GOC models and technology.


Assuntos
Dispositivos Lab-On-A-Chip , Microfluídica , Animais , Humanos , Modelos Animais
16.
Small ; 19(11): e2205744, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36634995

RESUMO

Thrombosis and its complications are responsible for 30% of annual deaths. Limitations of methods for diagnosing and treating thrombosis highlight the need for improvements. Agents that provide simultaneous diagnostic and therapeutic activities (theranostics) are paramount for an accurate diagnosis and rapid treatment. In this study, silver-iron oxide nanoparticles (AgIONPs) are developed for highly efficient targeted photothermal therapy and imaging of thrombosis. Small iron oxide nanoparticles are employed as seeding agents for the generation of a new class of spiky silver nanoparticles with strong absorbance in the near-infrared range. The AgIONPs are biofunctionalized with binding ligands for targeting thrombi. Photoacoustic and fluorescence imaging demonstrate the highly specific binding of AgIONPs to the thrombus when functionalized with a single chain antibody targeting activated platelets. Photothermal thrombolysis in vivo shows an increase in the temperature of thrombi and a full restoration of blood flow for targeted group but not in the non-targeted group. Thrombolysis from targeted groups is significantly improved (p < 0.0001) in comparison to the standard thrombolytic used in the clinic. Assays show no apparent side effects of AgIONPs. Altogether, this work suggests that AgIONPs are potential theranostic agents for thrombosis.


Assuntos
Nanopartículas Metálicas , Nanopartículas , Trombose , Humanos , Terapia Fototérmica , Prata , Nanopartículas Metálicas/uso terapêutico , Trombose/diagnóstico por imagem , Trombose/terapia , Imagem Multimodal/métodos , Nanopartículas Magnéticas de Óxido de Ferro , Nanomedicina Teranóstica/métodos , Fototerapia/métodos
17.
J Mater Chem B ; 11(12): 2650-2662, 2023 03 22.
Artigo em Inglês | MEDLINE | ID: mdl-36655707

RESUMO

This paper describes the preparation of poly(succinimide) nanoparticles (PSI NPs) and investigates their properties and characteristics. Employing direct and inverse precipitation methods, stable PSI NPs with tunable size and narrow dispersity were prepared without the use of any stabilizer or emulsifier. It was demonstrated that PSI NPs convert to poly(aspartic acid) (PASP) gradually under physiological conditions (37 °C, pH 7.4), while remaining stable under mildly acidic conditions. The dissolution profile was tuned and delayed by chemical modification of PSI. Through grafting a fluorophore to the PSI backbone, it was also demonstrated that such a spontaneous conversion could offer great potential for oral delivery of therapeutic agents to the colon. Sustained PASP synthesis also contributed to a sustained reduction of reactive oxygen species induced by iron. Furthermore, PSI NPs effectively prevented in vitro calcification of smooth muscle cells. This was attributed to the chelation of calcium ions to PASP, thereby inhibiting calcium deposition, because under cell culture conditions PSI NPs serve as reservoirs for the sustained synthesis of PASP. Overall, this study sheds light on the preparation and features of biocompatible and biodegradable PSI-based NPs and paves the way for further research to discover as-yet unfulfilled potential of this polymer in the form of nanoparticles.


Assuntos
Nanopartículas , Calcificação Vascular , Humanos , Ácido Aspártico/química , Cálcio , Nanopartículas/química , Succinimidas
18.
Cell Mol Life Sci ; 80(2): 46, 2023 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-36656411

RESUMO

Nanoceria or cerium oxide nanoparticles characterised by the co-existing of Ce3+ and Ce4+ that allows self-regenerative, redox-responsive dual-catalytic activities, have attracted interest as an innovative approach to treating cancer. Depending on surface characteristics and immediate environment, nanoceria exerts either anti- or pro-oxidative effects which regulate reactive oxygen species (ROS) levels in biological systems. Nanoceria mimics ROS-related enzymes that protect normal cells at physiological pH from oxidative stress and induce ROS production in the slightly acidic tumour microenvironment to trigger cancer cell death. Nanoceria as nanozymes also generates molecular oxygen that relieves tumour hypoxia, leading to tumour cell sensitisation to improve therapeutic outcomes of photodynamic (PDT), photothermal (PTT) and radiation (RT), targeted and chemotherapies. Nanoceria has been engineered as a nanocarrier to improve drug delivery or in combination with other drugs to produce synergistic anti-cancer effects. Despite reported preclinical successes, there are still knowledge gaps arising from the inadequate number of studies reporting findings based on physiologically relevant disease models that accurately represent the complexities of cancer. This review discusses the dual-catalytic activities of nanoceria responding to pH and oxygen tension gradient in tumour microenvironment, highlights the recent nanoceria-based platforms reported to be feasible direct and indirect anti-cancer agents with protective effects on healthy tissues, and finally addresses the challenges in clinical translation of nanoceria based therapeutics.


Assuntos
Antineoplásicos , Cério , Nanopartículas , Neoplasias , Espécies Reativas de Oxigênio/metabolismo , Estresse Oxidativo , Antioxidantes/metabolismo , Cério/farmacologia , Cério/uso terapêutico , Nanopartículas/uso terapêutico , Nanopartículas/química , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Oxigênio/farmacologia , Neoplasias/tratamento farmacológico
19.
ACS Biomater Sci Eng ; 9(6): 2846-2856, 2023 06 12.
Artigo em Inglês | MEDLINE | ID: mdl-33617219

RESUMO

Coenzyme-Q10 (CoQ10) is a hydrophobic benzoquinone with antioxidant and anti-inflammatory properties. It is known to reduce oxidative stress in various health conditions. However, due to the low solubility, permeability, stability, and poor oral bioavailability, the oral dose of CoQ10 required for the desired therapeutic effect is very high. In the present study, CoQ10 is encapsulated into two milk derived proteins ß-lactoglobulin and lactoferrin (BLG and LF) to produce self-assembled nanostructures of around 100-300 nm with high encapsulation efficiency (5-10% w/w). Both CoQ10-BLG and CoQ10-LF nanoparticles (NPs) significantly improved the aqueous solubility of CoQ10 60-fold and 300-fold, compared to CoQ10 alone, which hardly dissolves in water. Insight into the difference in solubility enhancement between BLG and LF was obtained using in silico modeling, which predicted that LF possesses multiple prospective CoQ10 binding sites, potentially enabling greater loading of CoQ10 on LF compared to BLG, which was predicted to be less capable of binding CoQ10. At pH 7.4, CoQ10-LF NPs showed a burst release between 30 min and 2 h then plateaued at 12 h with 30% of the total drug released over 48 h. However, pure CoQ10-BLG and pure CoQ10 had a significantly lower release rate with less than 15% and 8% cumulative release in 48 h, respectively. Most importantly, both BLG and LF NPs significantly improved CoQ10 permeability compared to the pre-dissolved drug across the Caco-2 monolayer with up to 2.5-fold apparent permeability enhancement for CoQ10-LF─further confirming the utility of this nanoencapsulation approach. Finally, in murine macrophage cells (J774A.1), CoQ10-LF NPs displayed significantly higher anti-ROS properties compared to CoQ10 (predissolved in DMSO) without affecting the cell viability. This study paves the way in improving oral bioavailability of poorly soluble drugs and nutraceuticals using milk-based self-assembled nanoparticles.


Assuntos
Antioxidantes , Nanopartículas , Humanos , Camundongos , Animais , Células CACO-2 , Estudos Prospectivos , Antioxidantes/metabolismo , Nanopartículas/química
20.
Small ; 19(9): e2204946, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36538749

RESUMO

Flexible and implantable electronics hold tremendous promises for advanced healthcare applications, especially for physiological neural recording and modulations. Key requirements in neural interfaces include miniature dimensions for spatial physiological mapping and low impedance for recognizing small biopotential signals. Herein, a bottom-up mesoporous formation technique and a top-down microlithography process are integrated to create flexible and low-impedance mesoporous gold (Au) electrodes for biosensing and bioimplant applications. The mesoporous architectures developed on a thin and soft polymeric substrate provide excellent mechanical flexibility and stable electrical characteristics capable of sustaining multiple bending cycles. The large surface areas formed within the mesoporous network allow for high current density transfer in standard electrolytes, highly suitable for biological sensing applications as demonstrated in glucose sensors with an excellent detection limit of 1.95 µm and high sensitivity of 6.1 mA cm-2  µM-1 , which is approximately six times higher than that of benchmarking flat/non-porous films. The low impedance of less than 1 kΩ at 1 kHz in the as-synthesized mesoporous electrodes, along with their mechanical flexibility and durability, offer peripheral nerve recording functionalities that are successfully demonstrated in vivo. These features highlight the new possibilities of our novel flexible nanoarchitectonics for neuronal recording and modulation applications.


Assuntos
Técnicas Biossensoriais , Eletrônica , Eletrodos , Monitorização Fisiológica , Porosidade
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA